Loop-forming device for sewing machines



10, 1929. a. s. GATCHELL 4 8,

I LOOP FORMING DEVICE FOR SEWING MACHINES Filed March 30, 1927 Patented Dec. 10, 1929 uinrre stares GEORGE s. GATGHELL, E EosELLE PARK, NEW JERsEY, ASSIGNOB. TO THE srneEE J 'VMANUFACTURING COMPANY, 0 ELIZABETH, NEW JERSEY, .A' CORPORATION 0E NEWJERSEY o LOOP-FORMING DEVICE FOR SEWI G MACHIN S end-wall of the cylinder-bed casting of the App1i'catioii filed March 30,1927. Serial No. 179,426.

This invention relates to sewing machines and more particularly to devices for insuring that the needle-tl1read loops will be formed at the proper side of the needle or needles for seizure by the loop-taker. V

An object of the invention is to provide a movable loop-forming device of simplified construction which may be applied to or removed from the machine as a unitary assembly independently of the machine mechanism and which, when appliech'will be operated by a moving part of the machine, without the necessity of providing the machine with a special driving connection for such device. A further object of the invention is to provide a movable loop-forming "device which is adapted for unitarily detachable mounting independently of the machine mechanism in a sewing machine having a rocking and sliding looper-shaft and, more specifically, with in the end-cap of a cylinder-bed sewing machine. A further object of the invention is to provide the device with means for'accurately adjusting its working positions.

To the attainment of the ends in view, the device, in its preferred embodiment, is constructed with a horizontally disposed supporting post, adapted to be attached to the machine below the looper-shaft. The supporting post pivotally carries at its outer end an upstanding holder for a fiat loop-engaging blade which is arranged to be moved to a Working position closely adjacent the outer side of the needle or needles.

As the needles rise the blade prevents expansion of the new needle-loops at the outer side of the needles and insures that the loops will expand fully at the inner sideof the needles in the path of the advancing looper. An adjusting screw carried by the pivoted holder bears upon a stop-lug on thepost to permit accurate adjustment of the working f position of the blade, adjacent the needles. A second adjusting screw carried by the holder is directed toward the end of the away from the outer side of the needles to clear the way for the looper.v

' 3', to shed the needle-loops.

In the accompanying drawings illustrating the invention in its preferred form, Fig. 1 is a side elevation, partly in section of the sewing end of a cylinder-bed chain-stitch sewing machine, with the looper advancing. Fig. 2 is a front end View. Fig.3 is a sideelevationof the stitch forming instrumentalities with the looper receding. Fig; 4 is a similar view with the needles in their lowest position.

1 represents the cylinder-bed of a sewing machine having ahead 2 carrying the needlebar 3 and a presser-bar 4 which carry, respectively, thereciprocating needles 5 and presser-foot 6. Cooperating with the presser-foot 6 to feed thework-is the four-motion feed-dog 7 carried by the feed-bar 8. Thethroat-platdis shownat 9 and'theen'd c-ap at' lO.

J'ournaled within andlengthwise of thecylin'der-bed 1 is the usual rocking and sliding looper-shaft '11 carrying the threaded looper 12' which 'advanc'es along the'inner to the post bears upon nr QFFHCE the receding movement; of V side of the needles to seizethe needle-loops, V

as shown in Figs; 1- and 2, andrecedes'along the'oute'r side of theneedles, as shown in Fig.

' Detachably' mounted on free end-wall of the bed 1 by screws 13 is the horizontally disposed supporting post 14: which pivotally carries at 15'thejholder 16 for the fiat loopen'g'a'ging blade '17 which is wide enough to engage the loops of both needles 5; The post 14; is formed with a stop-lug 18 for the ad- 7 j usting screw 19 "carried by the holder 16. c

. screw 21 The sprin secured to the post 14 by the ears, inwardly at its upwardly curved free end upon the holder 16 and biases the holder and loqJ-engaging blade'toward I needles. so'that as'the needles rise the needle-' the needles; the stop-screw 19 being adjusted to correctly positionthe blade 17 close to the loops will be caused to expand substantially.

wvholly atthe inner side of the needles. A

i second adjusting screw .22 carried'by'fthe tanceaW-ay from the needles to which the 2 loop-former will be shifted by .the loopershaft. This distance should'be just sufficient to ermit free passage of the looper blade. 7

t will be observed that in the position-of the parts shown ,in'Fig. 4 the looper-shaftis out of engagement with the end of the screw 22. Thus the looper-shaft partakes of acertain amount of endwise movement before it strikes the screw 22. and moves the loop-forming device. This intermittent contact between thelooper-shaft andthe screw 22 permits the loop-forming device to dwell or rescrew 22, v a V By removing the screws; 13 the complete main stationary I in loop-forming position while the needles are rising tothrow out their loops. The period of dwell of the loop-forming device may-be adjusted by adjusting the loop-forming device may be removed as a unitary assembly and, when replaced, will be operatively related to the looper-shaft to be properlyactuated by the latter without special or additional mechanism within the cylinder-bed where space isl at a premium.

. Having thus set forth the nature of the invention, what Iclaim herein is 1. The combination with a sewing machine having a reciprocating needle and a rocking andsli-ding looper-shaft, of .a loop-forming device detachably mounted as a unitar 1 ashaving a reciprocating needle and a rocking and sliding looper-shaft, of a loop-forming device including a pivotally mounted loop-' engaging member, an adjusting screw carried by said member and adapted to be engaged by the ilooper-shaft, during the latters sliding movement,-and a spring forbiasing said member toward the looper-shaft.

4. The combination with a sewing machine having a'reciprocating needle andra rocking "and slidinglooper-shaft, of aloop-formmg device including a pivotally mounted loop engaging member, an adjustable stop-screw carried by v said member, a stopengaged by "said screw to limit the movement of said loop -engaging member toward the needle, a spring for biasing said member to loop-engaging 77 position, and means for shifting said member away from said needle durlng the sliding movement oi the looper-shaft. f

j 5. The combination with a cylinder-bed sewing machine havlng a rec procating needle and a rocking and sliding looper-shaft disposed lengthwise of and within the cylinder-bed, of a supporting post detachably mounted on the free end-wall of the cylinder- 5 .bed below the looper-shaft, a loop-engaging member pivotally carried by said post, coacting stop andadjusting screw means carried by said post and member for determining'the loop-engaging position of the latter, a spring:

for biasing said member to loop-engaging position, and means for periodically shifting said member away from loop-engaging position. r

6. Thecombination with a sewing machine including a reciprocat ngneedle and fourmotion looper-mechanism, of a loop-forming device movably mounted adjacent the needlepath independently of the looper-mechanism and intermittently engaged andactuated by the looper-mechanism.

, In testimony whereof, I have signed my name to this specification.

IGEORGE .s. GATCHELL.

,semblyat the end of said looper-shaft, inde I 1 pendently of the sewing machine mechanism, U

3 and including a loop-engagingmember movable laterally. toward and, away from the needle in timed relation withv the advance andrecession of the looper 2. The combination with a'sewing machine j having a reciprocating needle and a rocking and sliding looper-shaft, ofvaloop forming device detachably mounted as a unitaryas- L sembly at the end of said looper-shaft and including a support, aloop-engaging member pivotally carried, by said support and adapted to be shifted by-endwise movement of the looper-shaft,

3. The combintion with aselwing machine, 1

d iz 5 

